1. Field of the Invention;
The present invention relates generally to a mold assembly for molding an article, and more particularly to such a mold assembly which is made of a hardened hydraulic material composition having high strength.
2. Related Art Statement;
Conventional molds or mold assemblies are made of cast irons, steels, zinc base alloys, aluminum or various resins. However, molds made of cast irons, steels, zinc base alloys or aluminum are expensive, since many cumbersome machining steps and long operation times are required for the production thereof. On the other hand, although a mold made of a resin can be fabricated relatively easily, a mold made of a resin cannot withstand a high temperature environment and hence cannot be used for molding a material which requires heating for hardening.
There is, therefore, a demand for a mold assembly which can be fabricated or shaped by a simple operation within a short time period and is excellent in durability.
Since cement concretes are moldable at room temperature and handled readily, they are used for various applications in the arts of civil engineering and building construction. However, any of the conventional cement mortars and concretes could not be used for making a mold or mold assembly, since they have insufficient strength of less than 1000 kgf/cm.sup.2 in compressive strength and tend to bleed or exhibit other material separation problems, leading to inferior profiling or shape-reproducing property.